Field of the Invention
The present invention relates to a non-contact power supply device, and to a processing apparatus that includes the non-contact power supply device and that is configured to convey an object to be processed such as a semiconductor wafer substrate and a glass substrate inside a closed container, and perform other processes.
Background Art
As a processing apparatus of this type, a processing apparatus including a movable body that is made movable by driving a linear motor has been conventionally proposed. Though not shown in the figures, a processing apparatus including a feed line arranged on a holder, a power supply transformer arranged to be opposed to the feed line directly thereabove, and a movable body placed on the power supply transformer via a member such as a base, for example, has been proposed. That is, the feed line and the power supply transformer in the processing apparatus are configured to be opposed to each other in a non-contact manner in the atmosphere.
Meanwhile, the object to be processed such as a semiconductor wafer substrate and a glass substrate is preferably processed under vacuum at a pressure lower than the atmospheric pressure. Therefore, the movable body is possibly housed in the closed container. As a processing apparatus configured to house a movable body in a closed container, a processing apparatus disclosed in JP 5470770 B, for example, has been proposed. In the processing apparatus according to this literature, a primary feed line is arranged outside the closed container capable of maintaining the vacuum state. Further, a power supply transformer configured to be supplied with power from the primary feed line in a non-contact manner and a movable body configured to move with the movement of the power supply transformer are arranged inside the closed container. That is, the power supply transformer is arranged along the primary feed line inside the closed container via a partition wall of the closed container.
In the processing apparatus of the above-described literature, a high-frequency current is allowed to flow through the primary feed line, and the number of magnetic flux is temporally changed, thereby allowing the primary feed line to be magnetically coupled to a secondary winding of the power supply transformer via the power supply transformer. As a result, a voltage is induced in the secondary winding of the power supply transformer, and electric power is supplied from the primary feed line to the secondary winding. Further, since the secondary winding is formed as a resonance circuit, the reactive power is reduced, and the power transmission efficiency is increased.
However, the magnetic coupling between the primary feed line and the secondary winding depends on the distance of the space present therebetween. Therefore, in the case where power is supplied to the secondary winding from the primary feed line via the partition wall, as in the processing apparatus of the above-described literature, the distance of the space present between the primary feed line and the secondary winding increases due to the presence of the partition wall. With the increase of the distance of the space, the power transmission efficiency from the primary feed line to the secondary winding decreases, which is a problem.
Therefore, in order to reduce the distance of the space present between the primary feed line and the secondary winding as much as possible, it is conceivable to arrange both the primary feed line and the power supply transformer (secondary winding) inside the closed container. According to this configuration, the two are directly opposed to each other without the partition wall to increase the coupling coefficient and to improve the transmission efficiency. However, this configuration has a problem of heat generation in the primary feed line and the secondary winding.
As heat dissipation methods, heat-conduction, convection, and radiation are generally known. However, in the closed container, which is a closed space, none of the heat dissipation methods may not be effective. In particular, when the inside of the closed container is under vacuum, heat dissipation by heat-conduction or convection is impossible, and even radiation is not an effective heat dissipation method. Then, heat generated in the primary feed line and the secondary winding as a loss remains inside the closed container. Such a problem occurs not only in the case of a processing apparatus in which the inside of the closed container is under vacuum, but also in the case of a processing apparatus in which the inside of the closed container is under atmospheric pressure in the same manner.